Slip elevator construction



Dec. 22, 1936. H. E. GRAU ET'AL SLIP ELEVATOR CONSTRUCTION 3 Sheets-Sheet '1' Filed Dec. 26, 1935 NvEN'roRs QM ATTORNEYS Dec. 22, 1936. H. E. GRAU ET AL 2,065,130

SLIP ELEVATOR CONSTRUCTION Filed Dec. 26, 1935 s Sheets-Sheet s J0 J2 J6 4 INVENTORS ATTORNEYS Patented Dec. 22, 1936 mm STATES PATENT OFFlCE stir smva'roa oons'rnuo'rlox Herbert Edmund Gran, Pasadena, Chester Albert Lnndeen, Los Angeles, and Glrd Elmer' Mullinix, South Gate, CaliL, assignors to Byron Jackson 00., Los Angeles, Calif., a corporation of Delaware Application December 26, 1935, Serial No. 56,164

18 Claims. (01. 24-263) This invention relates to elevators for raising and lowering pipe, rods and the like in wells and has to do more particularly with slip type elevators which grip the pipeor rod itself instead of merely engaging the under side of a collar or coupling on the pipe.

An object ofrthe invention is to automatically lift the slips of a slip'elevator out of pipe-engaging position in response to opening of the v 10 elevator.

Another object is to provide a simple and eti'ectiv'e structure for forcing the slips in opposite sides of an elevator to move simultaneously into and out of pipe engaging position. Another object is to provide a slip elevator in which the slips are maintained entirely clear of a pipe encircled by the elevator until the slips are released to engage the pipe, thereby preventing wear on the slip teeth which would otherwise result from sliding of the elevator up or down along the pipe priorto setting of the slips. Another object is to provide a slip elevator in which the pipe-engaging teeth on the slips are maintained clear of a pipewithin the elevator even after beingreleased if the elevator is moved downwardly along the pipe while at the same time the slip teeth are immediately forced into gripping engagement with the pipe in response to upward movement of the elevator along the Pipe. Another object is to automatically and positively force the slips of a slip type elevator into pipe-gripping position in response to movement of the elevator upwardly along a pipe into a position adjacent the collar or coupling on the upper end of the pipe.

The manner in whichthe foregoing together with other more specific objects of the invention are obtained, will appear from the following de- 40 scription.

As is well knownto those familiar with the art, slip elevators of the clas to which this invention relates, whether they be of the center latchorsidedoortype,-compriseapairofhinged in accordance with the present invention, we satisfy the foregoing requirements. by providing a cam mechanism which operates in response to opening movements of the body members of the elevator to retract the slips and provide a latch- 5 ing mechanism for thereafter retaining the slips in retracted position until it is desired to set 'the upper end of the pipe, or may be actuated manually through a line. We effect positive operation of the slips by so designing the latching mechanism that releasing movement thereof directly forces the slips downward into wedging 2 relation between the pipe and the body members of the elevator.

Wear of the slip teeth caused by the sliding movement of the elevator along the pipe is prevented in accordance with the invention by pro- 25 viding buil'er members resiliently supported on the individual slips, which buflermembers contact the pipe and resiliently urge theslipsaway from the pipe. When the slips are set, however,

these builer elements are forced back into re- 30 cesses provided therefor in the slips, permitting the slips to" engage the pipe.

For purposes of explanation, some preferred embodiments of the invention as incorporated in a center latch elevator will now be described 35 in detailwith reference to the drawings. It is to be understood, however, that many ieatures of the invention are equally applicable to side door elevators and that the invention is not to ac limited to elevators of center latch construc- 40 In thedrawings: Fig. 1 is a perspective view of a mantella slip elevator in accordance with the invention;

, Fig. 2 is a detail sectional view illustrating the 5 latch mechanism for locking the two halves of v the elevator together in closed position;

Fig. 3 is a horizontal sectional view. taken at the level III indicatedin Fig. .1; i

Fig.4isadetailhorizonta1sectional viewtaken 5 at the level rv in Fig. 1;

Fig. 'l is a detail vertical section illustrating the operation of the tripping mechanism of the elevator, showing the elevator with the slips in retracted position; and

Fig. 8 is a view similar to Fig. '7 but showing the slips released into pipe-engaging position.

Referring to Fig. 1, the elevator therein depicted comprises two main body members I and 2, respectively, which are hinged together at one end of each member by ahinge pin 3. As shown in Fig. l, the two members I and 2 are in open position ready tobe placed about a pipe. After being placed about a pipe the two members I and 2 are brought together as by the handles 4 and 5 thereon and locked in closed position by a latch 6 which engages lips I and 8, respectively, on the two body members I and 2. The particular latch construction disclosed is old and does not constitute a part of the present invention. It will sufiice to say that it is pivoted to the body member I by a hinge pin 9 and urged into closed position by a helical spring III. After it has been moved into engagement with the lips I and 8, it is locked in that position by a latch II pivotally mounted by a pin I2 on the member 6 and having a. latch bolt I3 which engages a. recess Il provided therefor in the lip 8. The latch mechanism described positively restrains the twobody members I and 2 against separating movement and is made sufliciently heavy to withstand the greatest separating strains to'which the elevator may. be subjected.

For the p se of supporting the elevator and a pipe suspended therefrom, ears I5 and II; are

provided projecting from the opposite sides of the members I and 2, respectively. Since the particular construction of these ears does-not constitute a part of the present invention, they have been shown partially broken away in Fig. 3. Each of the body members I and 2 is provided on its inner surface with a seat II slidably supporting two of four slips I8, I9, 20 and 2|.j As shown in Figs. '1 and 8, the surfaces of the slip seats I! are conical in shape and converge at their lower ends.- The cooperating surfaces of the slips are also conical in shape and curved 'to correspond approximately with their associated seating surfaces when they are in pipe-engaging position, as shown in Fig. 8.

It will be observed that in cross section each slip is wedge-shaped so that its pipe-contacting face 22 may contact with a pipe over its full length. Of course, the slips have their pipe-contacting faces cylindrically curved to correspond to the size pipe with which they are intended to be used. To secure the slips 2| in position against their respective seats I I, a retaining pin 23 is provided for each slip. Each pin 23 extends "through a hole 24 provided therefor in the eleposition by flanges 25 on pipe guides or bushings vator body member inwhich it is positioned, the pins being inserted from the top and retained in 26 which are bolted to the tops of the two body members I and 2, respectively. A small aperture 21 may be provided in the body members below the lower ends of the pins 23 to permit driving the pins upwardly and outwardly to facilitate replacing slips. Each pin 23 may also serve to secure in position alower pipe-contacting bushing 28. The upper and lower pipe-contacting bushings 26 and 28 are so dimensioned with respect to the size pipe with which the elevator is to be used as to prevent any substantial lateral movement of the elevator with respect to the pipe when the elevator is in closed position.

The pins 23' also pass through ears 30 on the seating faces of the slips and thereby retain the slips adjacent their seats. In order to provide room for the ears 30, the center lower portion of each slip seat I! is cut away to define a recess 3| in which the cars 30 are free to .move down. 7

It is sometimes desirable to resiliently urge the slips into seating position. To this end, a helical spring 32 may be provided around each pin 23 up and between the upper ear 39 thereon and the cosetting the slips so that it is not even necessary that the slips be urged downwardly by gravity.

By virtue of the fact that the cooperating surfaces of the slips and seats are conical, they can only contact uniformly over their entire surfaces .in one position. Therefore, in order to permit free sliding'movement of the slips on their associated pins 23, the apertures in the ears 30 for' the pins 23 aremade appreciably larger than the pins 'so that there is considerable free lateral movement of the slips with respect to the pins.

It is quite essential in a. slip elevator of the general type described that all of the slips move simultaneously into and out of seating position.

To this end, the two slips in each body member or notch in one edge of one slip and a cooperating tongue projecting from the juxtaposed edge of the I and 2, respectively, are linked together for simultaneous vertical movement by providing a recess other slip. Thus referring to Fig.3, it will be observed that the slip 20 is provided with a notch 40 projecting therefrom, (this notch being shown more clearly in Fig. 5), which notch engages a tongue 4| projecting from the edge of slip 2|.

- Likewise the slip I9 is provided with a tongue 42 which projects into a notch 43 in the edge of the slip I8. It will be observed, therefore, that slips I8 and I9 must move upwardly and downwardly together and likewise slips 20 and 2| must move upwardly and downwardly together.

To intercouple the slips in the two body members I and 2, respectively, for simultaneous vertical movement, other means must be employed be-' cause of the fact that the two body members I and 2 separate from each other during opening movement. The desired coupling is effected by providing an arcuate arm 44 of substantial length.

on the slip. 20, this arm being concentrically positioned with respect to the hinge pin 3 and extending a substantial distance thereabout in the general direction of the opposite body member I.

.The arm 44 intercepts the slip I 9 in body member regardless of whether the elevator is inopen or closed position. 7

To raise the slips I8 to 2|, inclusive, in response to opening of the elevator, the cam 46 is provided.

on the body member I, the cam extending helically with respect to the hinge pin 3. The cam 46 intercepts the adjacent edge of slip 20 and the slip is recessed to receive the cam so that the upper inclined surface 41 of cam 46 bears against a shoulder 48 at the upper'end of the recess 48 in slip 20, (this construction being shown clearly in Fi 5).

When the body members I and 2 are in closed position, the shoulder 48 rests upon the lower end of the cam surface 41, thereby permitting the slips to assume their lowermost, pipe-engaging position shown in Fig. 8. However, as the body members are swung apart to open the elevator, the shoulder 46 on slip 20 is forced to ride upwardly along the inclined surface of the cam, thereby lifting the slip 20, and of course simultaneously lifting the other three slips.

If no means were provided for securing the slips in uppermost position, they would fall into pipeengaging position each time the elevator was closed. In most instances, it is desired that the slips remain in retracted position after the elevator has been closed and be released either automatically or manually at a later time. Thus in some instances the elevator may be placed on the pipe at a point some distance below the upper end thereof whereas it is desired that the elevator grip the pipe at a point higher up. We therefore provide a latching mechanism for retaining the slips in the uppermost position to which they have been lifted by opening movement of the elevator.

This latching mechanism is shown in perspective in Fig. l and in section in Figs. 7 and 8. It

comprises a housing member 5|] bolted to the top of the elevator member 2 and extending thereabove an appreciable distance. member 5|] is provided with a slot-shaped recess at the upper end in which the bifurcated upper end of a supporting link 6| is positioned, which is formed integrally with the slip 2|. The link 6| is slidably supported within the member 50 for free vertical movement and for limited radial movement with respect to the axis of the elevator but is restrained against circumferential motion about the axis of the elevator. Supported between the bifurcated upper ends of the link 6| by a pin 52 is a latch member 5|. This latch member is constantly urged into the position shown in Fig. 7 by a helical spring 53 which fits in an arcuate slot 54 in the latch 5| and is compressed between one end wall 55 of the slot and a pin 56 anchored to the link 6|. Latch member 5| is provided with an arm or trigger 51 which extends almost but not quite into contact with a pipe positioned within the elevator, this pipe being indicated at 59 in Figs. 7 and-8. The end face 60 of arm 51 is preferably convexedly curved, in a vertical and curved concavedly in a horizontal planeabout the central axis of the elevator so that it conforms approximately to the curvature of the pipe 59.

' The latch member 5| is also provided with an arm 62 having an eye hole 63 therein for the attachment of a line and having a shoulder 64 thereon adapted to rest against a stop member 65 on the housing 56. It will be observed that the portion'of the arm 62 containing the eye 63 extends part way between the shoulder 64 and another shoulder 66 on the support 50. The latch 5| is normally supportedvertically by contact of the shoulder 64 with .the shoulder 65 as shown in Fig. '7. In this position the latch, through link 6|, supports the slip 2| in retracted position as shown in Fig. '7. Since as previously described, all of the slips are connected together,

This housing they will all be held in retracted position when the latch 5| is in the position shown in Fig. 7.

The slips may be released to engage the pipe by either of two methods. One method is to pull the arm 82 of latch 5| outwardly as by a line looped through the eye 63. This disengages the shoulder 64 from the shoulder 65, as shown in Fig. 8, thereby permitting the latch link 6| and the slip 2| to drop into the lower position shown in Fig. 8 in which the slips are in engagement with the pipe 59.

When it is desired that the slips be released automatically, the elevator, after being clamped about the pipe, is lifted up along the pipe with the slips retracted as shown in Fig. 7 until the 'arm 51 on the latch 5| impacts against the collar 65, the latch 5| will continue to rotate about the pin 52 until the ring 62 contacts the shoulder 66, whereupon further downward movement of the latch arm 51 forces the slips into engagement with the pipe 69.

The latch arrangement described has particular utility in connection with oil wells which produce large amounts of paraffin. The paraffin produces a thick viscous coating on the pipe or tubing as the latter is lifted out of the well and the paraffin is transferred from the tubing to the elevator, more or less completely filling all the spaces therewithin and preventing free movement of the slips. However, by employing the latch mechanism described and operating it automatically by lifting the elevator until the arm 51 engages the collar on the pipe, the slips are forced positively into engagement with the pipe regardless of any resistance to free movement of the slip caused by the paraflin.

It is important to note, however, in connection with the automatic operation of the latch as described, that by virtue of the fulcrum effect on the shoulder 66, the end of the arm 51 travels downwardly faster than does the slip 2| and the link 6|. As a result, when the slips engage the pipe and dig into the latter, they are then carried a short distance downward into full seating position directly by the pipe, the slip moving with the-pipe; This causes the arm 51 to move downwardly faster than the pipe so that when the slips have been set the arm 51 is always clear of the collar or coupling Ill. Hence during the actual lifting or lowering operation none of the weight of the pipe or tubing is transferred to the elevator through the collar and the latch arm 51.

Because of the difliculties in machining the parts and also by-reason of the fact that the slip seating surfaces are conical, the slips are always mounted rather loosely upon the pins 23, there often being suflicient play so that even when the slips are in retracted position as shown in Fig. 7, they may occasionally lightly contact a pipe as the elevator is being slid along the pipe. This is very objectionable because it occasions rapid wear of the teeth 22 on the faces of the slip and if the sharp surfaces of the teeth 22 are dulled the slips may then fail to properly grip the pipe. 7

To prevent accidental contact of the slip teeth with a pipe, with the slips in retracted position as shown in Fig. 7, we prefer to provide abow spring 80 on each slip, this spring being secured in a vertical recess extending along the face of the slip. The ends of the spring may be retained in grooves 8| positioned at the ends of the recesses in which the bow springs are mounted. The'centers of the bow springs project out beyond the cesses in the slips as shown in Fig. 8 so that they do not effect the normal setting operation of the slips.

It is sometimes desired to lower the elevator along the pipe with the slips released, to grip the pipe at a point lower down. Downward movement of the elevator with the slips released is, of course, possible because the friction of the pipe on the bow springs tends to carry the slips upwardly along their seats, thereby releasing them from wedging action against the pipe. However, this practice is objectionable with ordinary elevator constructions because it occasions wear on the slip teeth as a result of the friction with the pipe. However, by employing the bow springs 80 as disclosed in Figs. '7 and 8, and making these springs sufllciently stiff, they alone will contact the pipe during downward movement of the elevator along the pipe and will keep the teeth-of the slips clear of the pipe, thereby. preventing wear on the teeth.

To simplify the explanation of the invention,

- the latter has been described as incorporated in a particular type of elevator. It is obvious to those skilled in the art that various features of the invention may be incorporated in elevators of slightly different construction and the inven-'- tion is therefore to be limited only as set forth.

in the appended claims.

We claim:

l. A slip elevator of the type described comprising a pair of hinged pipe encircling members movable into closed and open positions-and means for locking said members in closed position, the

inner surfaces of said members having inwardly a cam on one of said members and -a cam fol-. lower on the other member. v

v 3. .A slip elevator as described in claim 1, in

which said means forlifting said slips comprises a'cam on one of said members and a cam follower on one ofsaid slips positioned on the other member, and means interconnecting all said slips for simultaneous movement.

4. A slip elevator of the type described comprising a pair of hinged pipe encircling members movable into closed and open positions and means for locking said members in closed position',.,the

inner surfaces of said members having inwardly and downwardly inclined slip seats thereomslips aooaiao slidably supported on said seats for downward movement therealong-into pipe-engaging positionand upward movement therealong out of pipe engaging position, means actuated by said members for lifting said slips out of pipe-engaging position in response to opening movement of said members, and latch means for releasably' retaining said slips out of pipe-engaging position during and following subsequent movement of said members into'closed position.

5. Aslip elevator of the type described comprising a pair of hinged pipe encircling members movable into closed and open positions and means for locking said members in closed position, the inner surfaces of said members having inwardly and downwardly inclined slip seats thereon, slipsslidably supported on said seats for downward movement therealong into pipe-engaging position and upward movement therealong out of pipe-engaging position, means actuated by. said members for lifting one of said slips outof pipeengaging position in response to opening movement of said members, and means interconnecting all said slips for simultaneous vertical movement.

6. A slip elevator as described in claim 5 in which said means interconnecting one slip on one of said members to a slip on said other member comprises an arcuate arm on one slip, said arm being concentric with respect to the hinged axis of the elevator and slidably engaging a slip on the other member to restrain the latter against vertical movement with respect to said arm.

'7. A slip elevator of the type described comprising a pair of hinged pipe encircling members movable into closed and open positions and means for locking said members in closed position, the inner surfaces of said members having inwardly and downwardly inclined slip seats thereon, slips slidably Supported on said seats for downward movement therealong into pipe-engaging position and upward movement therealong out of pipe-engaging position, a pipe-contacting member for eachslip, and means for yieldingly supporting each pipe-contacting member forward of the face of. its associated slip, each contacting member being retractable pwt the pipe-contacting face ofits associated slip in response to pressure exerted thereon.

8. Aslip elevator as described in claim 7; in which the slips are loosely slidably supported on their seats whereby they are capable of 2. limited amount of radial movement inwardly away from their seats.

9. A slip elevator as described in claim 7, in which the slips are loosely slidably supported on their seats whereby they are capable of a limited amount of radial movement inwardly away from their seats, and in whichsaid pipe-contacting members function when the elevator is positioned on a pipe to resiliently urge the slips away from the pipe and against their seats.

10. A slip elevator as described in claim I, in-

which said pipe-contacting members comprise bow springs mounted in vertical recesses provided therefor in the faces of the slips, the bow springs being positioned with their convex sides inwardly toward a pipe contained within the elevator and the ends of. the springs. being supported in the ends of the recesses. v

11. A slip elevator of the type described comprising .apair of hinged pipe encircling members movable intoclosed and open .positions' and means for locking-said members in'closed position, the inner surfaces of said members having inwardly and downwardly inclined slip seats thereon, slips slidably supported on said seats for downward movement therealong into pipeengaging position and upward movement there-- along out of pipe-engaging position, means actuated by said members for lifting said slips out of pipe-engaging position in response to opening movement of said members, latch means for releasably retaining said slips in uppermost position and trigger means associated with said latch in such position as to 'be engaged by a projection on the upper end ot a pipe encircled by the elevator when the latter is moved up along the pipe for releasing said latch means in response to contact of the trigger with the pipe projection. 12. A slip elevator of the type described comprising a pair of hinged pipe encircling members movable into closed and open positions and means forlocking said members in closed position, the

inner surfaces of said members having inwardly and downwardly inclined slip seats thereon, slips slidably supported on said seats for. downward movement therealong into pipe-engaging position and upward movement therealong out of pipe-m gaging position, means actuated by said members for lifting said slips out of pipe-engaging position in response to opening movement 01 said members, latch means mounted on one of said slips and cooperating with the member on which that slip is mounted, for releasably retaining said slips in uppermost position, and trigger means associated with said latch for releasing the latter.

13. A slip elevator as described in claim 11,

with means connecting said trigger to said slips whereby downward movement of said trigger positively moves said slips downward into pipeengaging position.

l 14. Aslip elevator as described in claim 12. in which said latch and trigger means comprises an arm secured to and extending upwardly from one of said slips, a lever member fulcrumed upon the upper end of said arm, said lever means comprising an arm extending toward the surface of a pipe engaged in the elevator and another arm extending substantially in the opposite direction, stationary means on said elevator for engaging said last mentioned arm in one position of said lever means, spring means for urging said lever means into said last mentioned position, said lever means being so mounted that downward movement of said first mentioned arm thereon disengages said second mentioned arm from said stop member whereby said arm and slip are released for free downward movement.

15. A [slip elevator as described in claim 12,

in which said latch and trigger means comprises an arm secured to and extending upwardly from one of said slips, a lever member fulcrumed upon the upper end of said arm,- said lever means comprising an arm extending toward the surface of a pipe engaged in the-elevator and another arm extending substantially in the opposite direction, stationary means on saidelevator for engaging said last mentioned arm in one position of said lever means, spring means for urging said lever means into said last mentioned position, said lever means being so mounted that downward movement of said first mentioned arm thereon disengages said second mentioned arm from said stop member whereby said arm and slip are released for free downward movement, and a secand frame member on said elevator positioned :above said last mentioned armon said lever memslips, respectively, said body members having holes for receiving said pins, extending from one end of the body member almost to the other end, the bushing at said one end overlying the open endof said hole whereby it prevents escape of the pin therein, and means for retaining said bushings on said body members.

17. A slip elevator as described in claim 16, in which the bushing at said other end of the body member has an apertured tongue engaged by said pin whereby the bushing is retained in place by the pin.

18. A- slip elevatorbf the type described comprising a pair of hinged pipe encircling body members movable into closed and open positions, the inner surfaces of said members having inwardly and downwardly inclined slip seats thereon, slips on said seat, pins for slidably retainingslips on said seats, pipe-contacting bushings on said body members above and below said slips, respectively, said upper pipe contacting bushings overlying the upper ends of said pins to prevent longitudinal' escape upwardly of the pins from the body members, means for securing the upper bushings on their associated body members, and means on the lower bushings for retaining them on their associated body members comprising apertured tongues intercepted by said pins whereby the lower bushings are retained in place by the pins.

HERBERT EDMUND GRAU. CHESTER ALBERT LUNDEEN. GIRD ELIVIER MULLINIX. 

